bruce



- A. W. BRUCE LOCOMOTIVE Filed May l5, 1925 Z'Sheets-Sheet I FIG. 1

MQWM/ Jan. 29, 1924. .1,482,115

A. W. BRUCE v LOCOMOTIVE Filed May l5, 1923 2 SheE'LS-Sheve'b 2 I lLWITNESSES @wf/ZW Patented Jan. 29, 1924.

UNITED STATES ALFRED W. BRUCE, or NEW YORK, N. Y.

LOCOMOTIVE.

Application filed May 15, 1923.

To @ZZ whom t may concern.'

Be it known that I, ALFRED W. Bauen, a citizen of the United States,residing at New York, in the county and State of New 6 York, haveinvented a certain new and use ful Improvement in Locomotives, of whichimprovement the following is a specification.

My invention relates to locomotive enin gines of the well known Mallet7type, in which two .independent groups of driving wheels are operated bythe pistons of separate pairs of cylinders, and its objects are (a), toenable an increase of tractive power to be attained within determinedwidth limits; (b), to attain a more even torque of the pistons of thelow pressure cylinders and reduce the liability7 to slipping of thegroup of "driving wheels actuated by them, and, 1 c), to enable anincreased reservoir capacity to be provided, without interference withnormal structural conditions.

The improvement claimed is hereinafter fully set forth.

In the accompanying drawings: Figure 1 is a diagrammatic side view, inelevation, of a Mallet locomotive engine in which my invention isapplied; Fig. 2, a plan or top view of the same, with the boilerremoved; and, Figs. 3 and 4, diagrammatic vertical transverse sections,on the lines and a a, respectively, of Fig. 1.

My invention is herein exemplified as applied in a compound Malletlocomotive, the boiler, 1, of which is, as in prior and presentpractice, supported on a rear group of eight driving wheels, 2,journalled in bearings in a main frame, 2, connected to the boilerwithout the capacity of relative lateral movement, and on a forwardgroup of driving wheels, 3, journalled in a supplemental frame, 3, whichis pivotally connected to the main frame, so as to have the capacity ofswivelling movement about the axial line of its pivotal connection,relatively there-to. The rear and front groups of driving wheels are, asheretofore, independently connected to, and rotated by, the pistons ofseparate sets of steam cylinders.

In the practice of my invention, referring descriptively to the specificembodiment thereof which is herein exemplified, steam, from the boiler,1, is supplied, through valve governed steam supply pipes, 5, 5a, to thevalve chests of a pair of high pressure Serial No. 639,044.

steam cylinders, 4, 12, supported on the main frame, 2a, the pistons ofwhich cylinders are coupled, in the usual manner, to one of the pairs ofdriving wheels of the rear group, 2, and steam is exhausted from saidcylinders into the valve chests of a set of low pressure steamcylinders, which consists of a middle cylinder, 6, and two sidecylinders, 6a, 6b, and is supported on the supplemental frame, 3a, ofthe locomotive. The pistons of the low pressure cylinders, 6, 6, and 6b,are coupled to crank pins on one of the axles of the driving wheels ofthe forward group, 3. A suitable intercepting valve mechanism, which maybe of any preferred known type, and does not form part of my presentinvention, will be understood to be interposed between the high and thelow pressure cylinders, as in present practice.

The exhaust steam from the high pressure cylinders, 4, 4a, is dischargedthrough an upwardly extending connecting pipe, 4P, into a receiver,composed of a transversely extending rear section, 7. located adjacentto the boiler, 1, and preferably, as shown, curved concentricallytherewith, and. two longitudinal sections, 7a, 7", extending, onopposite sides of the boiler, into a transverse front channel section,7, which is in continuously open communication with the valve chests, 8,8, and 8b, of the low pressure cylinders, 6, 6a and 6b, respectively. Asshown in Fig. 3, the channel section, 7. is cast integral with the lowpressure cylinders, but such specific structural form is not essential,as the channel section may, without departure from my invention, be madeas a separate pipe, connecting the two side sections with the valvechests of the low pressure cylinders.

It will be seen that the following substantial advantages are attainedby the application of my invention in a compound Mallet locomotive. Themore uniform torque and increase of tractive power' within determinedwidth limits, which have been proven to he resultant, in locomotives ofother types, have not heretofore' been available in Mallet locomotives,by reason of structural conditions, as the present receiver pipe somaterially obstructs the space between the side members of the forwardsupplemental frame as to prevent the installation of the valve operatingmechanism of three cylinl ders, as well as to interfere with the crankaXle and main connecting rod of the middle cylinder. The receiver of myinvention, hereinbefore described, being fully exempt from thisobjection, renders practicable the application. of three low pressurecylinders in Mallet locomotives, andl has the 'further advantage ofenabling the capacity ot' the receiver to be made as great as may befound desirable, Without involving the. use ot additional chambers andpipe connections, or presenting any interference With other members ofthe locomotive.

I claim as my invention and desire to secure by Letters Patent:

l. In a locomotive of the Mallet type, the combination of a rear groupof driving Wheels; a front group ot driving Wheels; two high pressurecylinders, the pistons ot Which actuate the rear group oi: drivingWheels; and three low pressure cylinders, the pistons of which actuatethe front group of driving Wheels.

2. In a locomotive of the Mallet type, the combination of a rear groupot driving Wheels; a -front group of driving Wheels; tivo high pressurecylinders, the pistons of which actuate the rear group of drivingWheels; three low pressure cylinders, the pistons of Which actuate thefront group of drivin Wheels; and a receiver, connecting the va vechests of the high and low pressure cylinders and extendinglongitudinally on opposite sides of the frame of the lou' pressurecylinders.

3. In a locomotive oi the Mallet type, the combination of high pressurecylinders; low pressure cylinders; and a receiver, connecting the valvechests of the high and louT pressure cylinders, and comprising atransverse rear section, connected to the valve chests of the highpressure cylinders,

two longitudinal side sections, and a frontl channel section connectedto the valve chests ot' the lovv pressure cylinders.

4t. In a locomotive of 'the Mallet type, the combination ot' two liighpressure cylinders; three low pressure cylinders; and a receiver,connected to the valve chests of the low pressure cylinders and having afront channel section continuously open to each of the valve chests ofthe low pressure cylinders.

5. In a locomotive ot the Mallet type, a receiver, composed ot' atransverse rear section; tivo longitudinal pipe sections spaced toextend outside the frame members of the engine; and a front channelsection, connecting the longitudinal sections and adapted for continuousopen communication With the valve chests of the loT pressure cylinders.

ALFRED W. BRUCE. Witnesses CONGER Munson, FRED. A, WADsWoR'rH.

